Mechanism for detachably attaching a timepiece movement to a watch casing, especially the middle ring thereof

ABSTRACT

A movement holder ring for resiliently attaching a timepiece movement to a watch casing by means of fixing means such as case screws or pins comprising the provision of a pair of inwardly projecting attaching tongues made integral with a ring flange which constitutes the holder ring, together with a web ring made integral therewith. These tongues are arranged substantially diametrally opposite to each other and has each such a configuration that they are brought into engagement with said respective fixing means when assembling of the holder ring and the watch movement in the interior of said watch casing. Said holder ring has several inwardly and outwardly and downwardly directing projections for assuring optimum contact with the movement as well as the watch housing, for keeping the movement in position and in a shock-absorbing way.

United States Patent [72] Inventors [21] Appl. No. [22] Filed [45] Patented [73] Assignee [54] MECHANISM FOR DETACHABLY ATTACHING A TIMEPIECE MOVEMENT TO A WATCH CASING, ESPECIALLY THE MIDDLE RING THEREOF 2 Claims, 9 Drawing Figs.

[52] US. Cl 58/94, 2 13 [5 1] Int. Cl G04b 37/04 [50] Field of Search 58/88 C,

[56] References Cited UNITED STATES PATENTS 37/191} 6 A EiQIQQ'QY LTtZ 1,995,951 3/1935 Straumann 58/88 C 3,520,130 7/1970 Oltramare 58/94 FOREIGN PATENTS 676,401 7/l 952 Great Britain 58/88.5 262,600 7/1949 Switzerland 58/88.5

Primary Examiner-Richard B. Wilkinson Assistant ExaminerGeorge H. Miller, Jr. AttorneySughrue, Rothwell, Mion, Zinn, & Macpeak ABSTRACT: A movement holder ring for resiliently attaching a timepiece movement to a watch casing by means of fixing means such as case screws or pins comprising the provision of a pair of inwardly projecting attaching tongues made integral with a ring flange which constitutes the holder ring, together with a web ring made integral therewith. These tongues are arranged substantially diametrally opposite to each other and has each such a configuration that they are brought into engagement with said respective fixing means when assembling of the holder ring and the watch movement in the interior of said watch casing.

Said holder ring has several inwardly and outwardly and downwardly directing projections for assuring optimum contact with the movement as well as the watch housing, for keeping the movement in position and in a shock-absorbing way.

PATENTEIJJm 1 m2 3,533,35

MECHANISM FOR DETACI-IABLY ATTACIIING A TIMEPIECE MOVEMENT TO A WATCH CASING, ESPECIALLY THE MIDDLE RING THEREOF This invention relates to improvements in and relating to a mechanism for detachably attaching a timepiece movement to a watch casing, especially the middle ring thereof. More specifically, it relates to improvements in the movement holder ring ofa watch.

It is commonly known to attach detachably a timepiece movement to a watch casing which has a separate or unitary back cover, as the case may be, by means of a movement holder ring inserted between the movement and the watch casing.

In order to adapt a standardized watch movement to a variety of watch casings in definite and reliable way, it is highly recommendable to use setscrews or pins for attaching the holder ring to the lower plate of the movement. These setscrews screws are called frequently case screws.

In this case, however, it is a common and more frequently employed practice to use a separate and independent bridging metallic strip for mechanically connecting the watch casing or the holder ring, as the case may be, with the movement under axially pressurized way, the case screw penetrating through one end of said strip into the plate of the movement.

According to our practical experience, however, it has been found that the aforementioned conventional structure of the attaching mechanism between the watch movement and the casing using the bridging strip provides a highly troublesome workmanship as well as a time-consuming assembly procedure, especially invited by indefinitely directional positioning of the strip.

In the above-mentioned structure, it is further highly recommendable to bring the movement holder ring into its positively preselected position in its circumferential direction, so as to avoid an invitation of an excess frictional resistance to the conventional winding stem of the watch during a time-setting, sprin g-windin g or calendar-correcting manipulation.

It is still further recommended to provide the movement holder ring with a possibility for attaining a predetermined radial as well as axial position relative to the movement.

These and further objects, features and advantages of the invention will become more apparent when read in the following detailed description by reference to the accompanying drawings.

In the drawings:

FIG. 1 is a perspective view of a preferred embodiment of a movement holder ring which constitute a main and substantial part of the movement attaching mechanism according to this invention.

FIG. 2 is a part of a cross section of the movement holder ring, taken substantially along a section line 11-11 shown in FIG. 1, wherein, however, part of a conventional dial plate and a conventional watch movement are additionally shown.

FIG. 3 is a part of an axial section of a watch wherein the movement holder ring has been inserted in position.

FIGS. 46 are respective plan views of several modified attaching tongues projecting inwardly and radially from the movement holder ring proper.

FIG. 7 is a similar view to FIG. 4, showing a still modified form of the attaching tongue adapted for cooperation with a positioning pin in place of a case screw.

FIG. 8 is a similar view to FIG. 2, showing, however, the still modified form of the attaching tongue illustrated in FIG. 7.

FIG. 9 is a similar view to FIG. 7, illustrating, however, a still modified form of the attaching pin.

Referring now to the accompanying drawings, especially FIGS. 1 and 2 thereof, the numeral 10 generally denotes a movement holder ring which comprises a ring web 11 and a ring flange 12 made integral therewith, said web being interrupted at two positions 13 and 14 positioned substantially diametrally opposite to each other.

A pair of attaching tongues 16 and 17 project from the material of the ring flange 12 in a shouldered way and at a slightly lower level. These tongues 16 and 17 are arranged substantially in a diametrally opposite way, as seen from FIG. 1. These tongues are formed with respective screw-receiving openings 16a and 17a, respectively. The holder ring 10 is made from a tough and elastic material such as a stainless steel sheet by a combined punching and drawing two-step press job.

At both sides of each of the attaching tongues 16 and 17, there are provided a pair of inwardly directing small projections 18;l9 or 20;2l, respectively, for snugly contacting with the circumferential wall of the watch movement 22 shown in FIG. 3 as an example.

Similar inward projections are also formed at 23, 24 and 25.

The web 11 is formed with a plurality of circumferential and elongated grooves 26, 27 and 28 arranged circumferentially one after another and at certain mutual distances one after another, for providing an enough degree of elasticity to the holder ring 10 per se, to absorb occasionally encountering outside shocks applied to the movement through the watch casing and the holder ring when assembled together and while in use.

For each of the peripheral grooves 26 -28, at substantially midway thereof, there is formed a depending projection 29, 30 or 31, respectively, adapted for contact with the inside wall surface of the back cover such as at 32 in FIG. 3.

A pair of peripheral enlarged edges 33 and 34 are formed on the ring flange 12 in the integral manner, the center of each of these edges when seen in the peripheral direction of the holder ring 10 being situated on a diameter thereof which is drawn at substantially right angles connecting the pair of the attaching tongues 16 and 17. These elongated edges 33 and 34 are arranged to contact with the inside wall of the casing, as at 35 in FIG. 3, of the watch. In practice, however, practically the whole outer periphery of the ring flange 12 is brought into contact with the inside wall surface of the watch casing, on account of the diametral expansion of the holder ring 10 in the diametral direction connecting the both tongues 16 and 17, appearing when and after assembly of the holder ring in position by tightening the case screws 36 in position, as will be more fully described hereinafter by reference to FIG. 2.

In FIG. 3, the numeral 37 denotes a crystal or watch glass; 38 a seconds hand; 39 a minute hand; 40 an hour hand; 41 a dial plate; 42 a winding stem; and 43 a crown. These parts are conventional and thus no further analysis would be necessary for understanding of the invention.

In FIG. 2, the numeral 44 represents a conventional plate of the watch movement generally shown at 22, said plate being formed with two tapped holes for threadedly receiving respective case screws 36. In FIG. 2, however, one of these case screws 36 and its mating tapped hole 45 only are shown.

For receiving each of the attaching tongues 16 and 17, the plate 44 is formed with a recess 46 one side edge 46a of which is adapted for serving as effective means for circumferential positioning of the holder ring 10, as will be easily supposed from FIG. 4.

For performing the assembly of the holder ring 10 in position, the casing 35 attached with dial plate 41 and glass 37 is inverted up and down in its position from that shown in FIG. 3 and then the back cover 32 is removed from the casing for exposing the interior space thereof. Then, the movement 22 is inserted from upper in position and the holder ring 10 is positioned between the outer periphery of the movement and the inside wall of the middle ring 35 of the watch casing in such a way that each of the attaching tongues l6-l7 is positioned within the area of the related recess 46 on the plate 44. Next, the holder ring 10 is slightly rotated until the tongue 16 or 17 has been brought into contact with the positioning side edge 46a of the recess 46. It will be easily supposed that the tapped hole 45 is brought into registration with the screw-receiving hole 16a of the tongue 16. This is applied to the case of the opposite tongue 17. The inward projections I8, 19, 20, 21, 23, 24 and 25 have been brought until this stage into intimate contact with the outer peripheral wall surface of the movement.

Then, case screws 36 are inserted through the receiving openings 16a and 17a into the respective tapped holes 45 and then tightened. As was referred to hereinbefore, the holder ring is expanded in a specific diametral direction along the line connecting the tongues 16 and 17 by tightening said screws 36, but, this is compensated to a substantial degree by the provision of two elongated enlarged edges 33 and 34, thereby substantially all the outer periphery of the ring flange 12 will be brought into contact with the inner wall surface of the middle ring 35. In this way, an optimum and resilient positioning of the movement 22 by the holder ring is assured, in spite of the forced deformation of the ring caused by tightening of the case screws.

Finally, the removed back cover 32 is attached back in position, as shown in FIG. 3. By this procedure, the axially depending projections 29-31 are brought into pressure contact with the ring shoulder 32a formed on the inside wall surface of the back cover 32. In this way, the holder ring 10 having an axially resilient structure attained by the provision of several separated and elongated peripheral grooves 2628, is resiliently compressed in axial direction to a certain degree, thus the movement 22 being positioned in an optimum manner and under resiliently pressurized condition, for absorbing occasional outside shocks.

At the initial stage of the assembly of the holder ring 10 in the aforementioned manner, the stem 42, which has been shown only partially for avoiding the complexity of the drawing, is introduced through the interruption into a peripheral groove 47.

By turningly positioning of the holder ring 10 in the aforementioned way, the stem will be submerged into the said groove 47. In this way, the stem may be kept in its proper position for avoiding excess rotational resistance by contact with the holder ring 10.

The dismantling of the holder ring 10 and the movement 22 from the watch casing 35 attached with glass 37 and back cover 32 may be carried into effect in the reverse order.

FIG. 4 shows a modified form of the attaching tongue at 116 which is formed with a fork fingers 116a and 116b in place of the foregoing screw-receiving hole 16a. The fork groove 116a formed between the fingers 116a and 116k serves well as the screw-receiving means. Naturally, the width of the groove 1160 is so selected well to support the enlarged head at 36a of case screw 36 by the fork fingers 116a and 116b. The similar feature is also applied to the opposite tongue, although not shown.

The dimension of the hole 16a or 17a is naturally selected to prevent a slip-in of the enlarged head as at 36a of the case screw.

FIG. 5 is a still further modified form of the case screw at 116 which is, however, substantially similar to that shown in FIG. 4. In the present modification, one ofthe fork fingers 16a has a shorter length than the other finger 116b" for easier catch of the case screw 36. The opposite tongue may have naturally the same structure, although not shown.

The still modified tongue at 116 shown in FIG. 6, it is formed into a substantially rectangular configuration in its plan view. This tongue 116" is so dimensioned that upon assemble of the movement holder ring 10, a part of the enlarged head 36a of the case screw 36 is kept in pressure abutment against the inner and straight end edge 116a" of the tongue. Thus, a more easy engagement of the case screw with the tongue is assured when assembling of the holder ring in position.

In the embodiment shown in FIGS. 7 and 8, the attaching tongue at 216 having fork fingers 216a and l16b defining an open groove 2166 is substantially similar to that shown in FIG. 4. In the present embodiment, the tongue is so designed and dimensioned so as to cooperate with a case pin 136 which is held in position by insertion in a plain hole bored through the plate 44 in place of the foregoing tapped hole 45. The case pin 136 has a tapered head 136a which has such a diametral dimension that when the forked tongue 216 is forcibly pressed in the axial direction of the watch the groove 2160 is elastically and provisionally expanded for allowing passage of the tapered pinhead 136a through the groove. Upon such forced passage, the pinhead is caught by the now recontracted groove 216C. The edge 46a of the recess 46 serves for initial and circumferential positioning of the holder ring 10 by cooperation with one side straight edge portion 216d of the tongue.

In the final embodiment shown in FIG. 9, the pinheadreceiving groove 216c'is formed laterally of the tongue 216'.

The purpose of this lateral groove 2160' in place of the axial groove 216C in the foregoing would be self-explanatory by comparing the chain dotted line position with the full line one shown in FIG. 9. More specifically, the purpose is for lateral catch of the case pin by the catching groove 216a by an initial turning of the holder ring 10. The recess 46' on the plate 44 in this embodiment is selected to have a substantially larger area than the foregoing recess 46.

The embodiments of the invention in which an exclusive property or privilege is claimed are as follows:

1. Mechanism for detachably attaching a timepiece movement to a watch casing, especially the middle ring thereof by means of a holder ring, said mechanism being characterized by that said holder ring comprising an interrupted web ring, an interrupted ring flange made integral therewith, a plurality of separated inward projections formed integral with said ring flange and adapted for contact with the outer peripheral surface of said movement, a plurality of elongated circumferential grooves for providing an axial resiliency to said holder ring, a plurality of separated depending projections formed on the ring web and adapted for contact with a back cover of said watch, and a pair of inwardly projecting tongues made integral with said ring flange and arranged substantially diametrally opposite to each other, the main part of each of said tongues being positioned at a slightly lower level than that of said ring flange and said tongues being so shaped that they engage with fixing means mounted on the plate of said movement.

2. Mechanism as set forth in claim 1, characterized in that said ring flange is formed with a plurality of enlarged edges made integral therewith and each extending a substantial circumferential length of the holder ring, said edges being adapted for contacting with the inside wall surface of the middle ring of the watch casing in such manner that a forced elastic deformation of the holder ring as appearing upon assembly of the later by said fixing means is substantially compensated for. 

1. Mechanism for detachably attaching a timepiece movement to a watch casing, especially the middle ring thereof by means of a holder ring, said mechanism being characterized by that said holder ring comprising an interrupted web ring, an interrupted ring flange made integral therewith, a plurality of separated inward projections formed integral with said ring flange and adapted for contact with the outer peripheral surface of said movement, a plurality of elongated circumferential grooves for providing an axial resiliency to said holder ring, a plurality of separated depending projections formed on the ring web and adapted for contact with a back cover of said watch, and a pair of inwardly projecting tongues made integral with said ring flange and arranged substantially diametrAlly opposite to each other, the main part of each of said tongues being positioned at a slightly lower level than that of said ring flange and said tongues being so shaped that they engage with fixing means mounted on the plate of said movement.
 2. Mechanism as set forth in claim 1, characterized in that said ring flange is formed with a plurality of enlarged edges made integral therewith and each extending a substantial circumferential length of the holder ring, said edges being adapted for contacting with the inside wall surface of the middle ring of the watch casing in such manner that a forced elastic deformation of the holder ring as appearing upon assembly of the later by said fixing means is substantially compensated for. 